U.S. patent number 10,226,912 [Application Number 14/371,938] was granted by the patent office on 2019-03-12 for intermediate film for laminated glass, and laminated glass.
This patent grant is currently assigned to SEKISUI CHEMICAL CO., LTD.. The grantee listed for this patent is SEKISUI CHEMICAL CO., LTD.. Invention is credited to Shota Matsuda, Michio Shimamoto, Sinyul Yang.
United States Patent |
10,226,912 |
Shimamoto , et al. |
March 12, 2019 |
Intermediate film for laminated glass, and laminated glass
Abstract
An interlayer film for laminated glass that can improve a sound
insulation property of an obtained laminated glass when the
interlayer film for laminated glass is used for configuring the
laminated glass is provided. The interlayer film for laminated
glass according to the present invention includes a first layer and
a second layer laminated on a first surface of the first layer. The
first layer includes a polyvinyl acetate resin and a
plasticizer.
Inventors: |
Shimamoto; Michio (Kouka,
JP), Matsuda; Shota (Osaka, JP), Yang;
Sinyul (Osaka, JP) |
Applicant: |
Name |
City |
State |
Country |
Type |
SEKISUI CHEMICAL CO., LTD. |
Osaka, Osaka |
N/A |
JP |
|
|
Assignee: |
SEKISUI CHEMICAL CO., LTD.
(Osaka, JP)
|
Family
ID: |
48781598 |
Appl.
No.: |
14/371,938 |
Filed: |
January 11, 2013 |
PCT
Filed: |
January 11, 2013 |
PCT No.: |
PCT/JP2013/050463 |
371(c)(1),(2),(4) Date: |
July 11, 2014 |
PCT
Pub. No.: |
WO2013/105657 |
PCT
Pub. Date: |
July 18, 2013 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20150030860 A1 |
Jan 29, 2015 |
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Foreign Application Priority Data
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Jan 13, 2012 [JP] |
|
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2012-005319 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
C08K
5/11 (20130101); B32B 17/10036 (20130101); B32B
17/10761 (20130101); C08K 5/0016 (20130101); B32B
17/10605 (20130101); B32B 2307/102 (20130101); Y10T
428/31649 (20150401); B32B 2331/04 (20130101); Y10T
428/31859 (20150401); Y10T 428/31935 (20150401); B32B
2250/40 (20130101) |
Current International
Class: |
C08K
5/11 (20060101); B32B 17/10 (20060101); C08K
5/00 (20060101) |
Field of
Search: |
;428/442,501,522,441,515,523 ;524/563 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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101637991 |
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Feb 2010 |
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CN |
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1 281 690 |
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Feb 2003 |
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EP |
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461684 |
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Feb 1937 |
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GB |
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470135 |
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Aug 1937 |
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GB |
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471904 |
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Sep 1937 |
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GB |
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821537 |
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Oct 1959 |
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GB |
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1 516 869 |
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GB |
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37-18625 |
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Dec 1962 |
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JP |
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51-84878 |
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JP |
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8-59306 |
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Mar 1996 |
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JP |
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11-287797 |
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2000-247690 |
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JP |
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2003-252655 |
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JP |
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2005-502512 |
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JP |
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2006-278445 |
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Oct 2006 |
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JP |
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2006-290948 |
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Oct 2006 |
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JP |
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2007-70200 |
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Mar 2007 |
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JP |
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2007-253469 |
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Oct 2007 |
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JP |
|
2009-161584 |
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Jul 2009 |
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JP |
|
2009161584 |
|
Jul 2009 |
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JP |
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2011-42552 |
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Mar 2011 |
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JP |
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2011-207762 |
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Oct 2011 |
|
JP |
|
Other References
Machine translation of JP 2009161584 A, retrieved Jul. 9, 2016.
cited by examiner .
International Search Report for the Application No.
PCT/JP2013/050463 dated Apr. 16, 2013. cited by applicant .
Written Opinion of the International Searching Authority
(PCT/ISA/237) for Application No. PCT/JP2013/050463 dated Apr. 16,
2013. cited by applicant .
The First Office Action for the Application No. 201380002680.4 from
the State Intellectual Property Office of the People's Republic of
China dated Aug. 26, 2015. cited by applicant .
Supplementary European Search Report for Application No. EP 13 73
6084 dated Jul. 15, 2015. cited by applicant .
Written Opinion of the International Searching Authority
(PCT/ISA/237) for the Application No. PCT/JP2013/050463 dated Apr.
16, 2013 (English Translation mailed Jul. 24, 2014). cited by
applicant .
The Second Office Action for the Application No. 201380002680.4
from the State Intellectual Property Office of the People's
Republic of China dated Mar. 28, 2016. cited by applicant.
|
Primary Examiner: Shosho; Callie E
Assistant Examiner: Shukla; Krupa
Attorney, Agent or Firm: Cheng Law Group, PLLC
Claims
The invention claimed is:
1. An interlayer film for laminated glass comprising: a first
layer; a second layer laminated on a first surface of the first
layer; and a third layer laminated on a second surface opposite to
the first surface of the first layer, wherein the first layer
comprises a combination of a thermoplastic resin and a plasticizer,
the thermoplastic resin in the first layer consists essentially of
a polyvinyl acetate homopolymer resin, a polymerization degree of
the polyvinyl acetate homopolymer resin in the first layer is 1500
or more and 15,000 or less, the plasticizer in the first layer is
at least one of (a) triethylene glycol di-n-butanoate, (b)
triethylene glycol di-n-propanoate, and (c) an ester compound of
adipic acid and an alcohol having a linear or a branched structure
having a carbon number of 4 to 8, the combination of the polyvinyl
acetate homopolymer resin and the plasticizer comprised in the
first layer has a cloud point of 80.degree. C. or less when the
cloud point is measured using a solution in which 8 parts by weight
of the polyvinyl acetate homopolymer resin is dissolved in 100
parts by weight of the plasticizer, the second layer comprises a
polyvinyl acetal resin and a plasticizer, the polyvinyl acetal
resin in the second layer has an acetylation degree of 15 mol % or
less and a hydroxyl group content of 20 mol % or more, the
plasticizer in the second layer is at least one of (a) triethylene
glycol di-n-butanoate, (b) triethylene glycol di-n-propanoate, and
(c) an ester compound of adipic acid and an alcohol having a linear
or a branched structure having a carbon number of 4 to 8, and a
content in parts by weight of the plasticizer in the second layer
to 100 parts by weight of the polyvinyl acetal resin in the second
layer is 5 parts by weight or more 50 parts by weight or less.
2. The interlayer film for laminated glass according to claim 1,
wherein the first layer comprises a tackifier.
3. The interlayer film for laminated glass according to claim 2,
wherein the first layer consists essentially of the thermoplastic
resin, the plasticizer, and the tackifier.
4. The interlayer film for laminated glass according to claim 1,
wherein the third layer comprises a polyvinyl acetal resin; and the
polyvinyl acetal resin in the third layer has an acetylation degree
of 15 mol % or less and a hydroxyl group content of 20 mol % or
more.
5. The interlayer film for laminated glass according to claim 4,
wherein the first layer comprises a tackifier; and the tackifier is
a rosin resin.
6. The interlayer film for laminated glass according to claim 1,
wherein a thickness of the first layer is 0.02 mm to 0.5 mm, a
thickness of the second layer is 0.1 mm to 0.5 mm, and a thickness
of the third layer is 0.1 mm to 0.5 mm.
7. The interlayer film for laminated glass according to claim 1,
wherein a content in parts by weight of the plasticizer in the
second layer to 100 parts by weight of the polyvinyl acetal resin
in the second layer is less than a content in parts by weight of
the plasticizer in the first layer to 100 parts by weight of the
polyvinyl acetate, homopolymer resin in the first layer.
8. The interlayer film for laminated glass according to claim 7,
wherein the third layer comprises a polyvinyl acetal resin and a
plasticizer, a content in parts by weight of the plasticizer in the
third layer to 100 parts by weight of the polyvinyl acetal resin in
the third layer being less than the content in parts by weight of
the plasticizer in the first layer to 100 parts by weight of the
polyvinyl acetate homopolymer resin in the first layer.
9. The interlayer film for laminated glass according to claim 8,
wherein an absolute value of a difference between (A) the content
in parts by weight of the plasticizer in the first layer to 100
parts by weight of the polyvinyl acetate resin in the first layer
and each of (B1) the content in parts by weight of the plasticizer
in the second layer to 100 parts by weight of the polyvinyl acetate
homopolymer resin in the second layer, and (B2) the content in
parts by weight of the plasticizer in the third layer to 100 parts
by weight of the polyvinyl acetal resin in the third layer is 5
parts by weight or more.
10. A laminated glass comprising: a first component for laminated
glass, a second component for laminated glass, and an interlayer
film sandwiched between the first component for laminated glass and
the second component for laminated glass, wherein the interlayer
film is the interlayer film for laminated glass according to claim
1.
Description
TECHNICAL FIELD
The present invention relates to an interlayer film for laminated
glass used for automobiles and architectural structures and the
like, and more particularly relates to an interlayer film for
laminated glass containing a thermoplastic resin and a plasticizer.
In addition, the present invention relates to a laminated glass
made by using the interlayer film for laminated glass.
BACKGROUND ART
A laminated glass has excellent safety because a flying amount of
broken pieces of glass is small if the laminated glass was broken
by being subject to external impact. Therefore, the laminated glass
is widely used for automobiles, railway cars, aircraft, ships, and
architectural structures and the like. The laminated glass is
manufactured by sandwiching an interlayer film between a pair of
glass plates.
In recent years, reduction in the thickness of the laminated glass
has been studied in order to reduce the weight of the laminated
glass. When the thickness of the laminated glass is reduced,
however, a sound insulation property is deteriorated. When the
laminated glass having a low sound insulation property is used for
a windshield of an automobile and the like, a problem that a
sufficient sound insulation property for sound in a sound range of
about 5000 Hz such as wind noise and driving noise of wipers cannot
be obtained arises.
Consequently, improvement of the sound insulation property of the
laminated glass by modifying materials of the interlayer film has
been studied.
As one example of the interlayer film for laminated glass, Patent
Document 1 discloses a sound insulation layer including 100 parts
by weight of a polyvinyl acetal resin having an acetalization
degree of 60 to 85 mol %, 0.001 to 1.0 parts by weight of at least
one metal salt of alkaline metal salts and alkaline earth metal
salts, and 30% by weight or more of a plasticizer. The sound
insulation layer is used as a single layer interlayer film or a
multi-layer interlayer film formed by laminating with other
layers.
RELATED ART DOCUMENT
Patent Document
Patent Document 1: JP 2007-070200 A
SUMMARY OF THE INVENTION
Problems to be Solved by the Invention
Although the laminated glass made by using the interlayer film
described in Patent Document 1 described above can improve the
sound insulation property to some extent, further improvement of
the sound insulation property is required.
The sounds to be insulated by the interlayer film include air-borne
sound such as noise of an automobile and sound of a horn and
solid-borne sound such as sound of vibration of an engine of an
automobile. The laminated glass using the interlayer film described
in Patent Document 1 may not sufficiently improve the sound
insulation property for the solid-borne sound in particular.
In recent years, substitution from a fuel vehicle using an internal
combustion engine to an electric vehicle using an electric motor
and a hybrid electric vehicle using an internal combustion engine
and an electric motor has proceeded. For the laminated glass used
for the fuel vehicle using the internal combustion engine, the
sound insulation property relatively in a low frequency range is
particularly required. For the laminated glass used for the fuel
vehicle using the internal combustion engine, however, the high
sound insulation property in a' high frequency range is also
desired. On the contrary, for the laminated glass used in the
electric vehicle and the hybrid electric vehicle using the electric
motor, the high sound insulation property in the high frequency
range is particularly required in order to effectively cut off the
driving sound of the electric motor.
When the laminated glass is configured by using the interlayer film
described in Patent Document 1, the laminated glass has an
insufficient sound insulation property in the high frequency range,
and thus, deterioration in the sound insulation property caused by
a coincidence effect may not be avoided. In particular, the
laminated glass may have an insufficient sound insulation property
at about 20.degree. C.
Here, the coincidence effect is a phenomenon in which, when sound
waves are incident into a glass plate, resonance of a transverse
wave and the incident sound is generated by propagating the
transverse wave on the grass surface due to rigidity and inertia of
the glass, and as a result, transmission of the sound occurs.
In recent years, addition of an excessive amount of plasticizer to
the interlayer film has also been studied in order to improve the
sound insulation property of the laminated glass. The sound
insulation property of the laminated glass can be improved by
adding the excessive amount of the plasticizer to the interlayer
film. Use of the excessive amount of the plasticizer, however, may
cause the plasticizer to bleed out to the surface of the interlayer
film.
The purpose of the present invention is to provide the interlayer
film for laminated glass that can improve the sound insulation
property of the obtained laminated glass when the interlayer film
is used for configuring the laminated glass, and the laminated
glass made by using the interlayer film for laminated glass.
The limited purpose of the present invention is to provide the
interlayer film for laminated glass that can improve the sound
insulation property in the high frequency range of the obtained
laminated glass when the interlayer film is used for configuring
the laminated glass, and the laminated glass made by using the
interlayer film for laminated glass.
Means for Solving the Problems
According to a broad aspect of the present invention, an interlayer
film for laminated glass including a first layer; and a second
layer laminated on a first surface of the first layer, wherein the
first layer includes a polyvinyl acetate resin and a plasticizer is
provided.
In a particular aspect of the interlayer film for laminated glass
according to the present invention, the polyvinyl acetate resin and
the plasticizer included in the first layer are a polyvinyl acetate
resin and a plasticizer having a cloud point of 80.degree. C. or
less that is measured by using a solution in which 8 parts by
weight of the polyvinyl acetate resin is dissolved in 100 parts by
weight of the plasticizer.
In another particular aspect of the interlayer film for laminated
glass according to the present invention, the first layer includes
a tackifier.
In further another particular aspect of the interlayer film for
laminated glass according to the present invention, the second
layer includes a polyvinyl acetal resin and the polyvinyl acetal
resin in the second layer has an acetylation degree of 15 mol % or
less and a hydroxyl group content of 20 mol % or more.
In another particular aspect of the interlayer film for laminated
glass according to the present invention, the interlayer film
further includes a third layer laminated on a second surface
opposite to the first surface of the first layer, wherein the third
layer includes a polyvinyl acetal resin and the polyvinyl acetal
resin in the third layer has an acetylation degree of 15 mol % or
less and a hydroxyl group content of 20 mol % or more.
In further another particular aspect of the interlayer film for
laminated glass according to the present invention, the first layer
includes a tackifier, wherein the tackifier is a rosin resin.
A laminated glass according to the present invention includes a
first component for laminated glass; a second component for
laminated glass; and an interlayer film sandwiched between the
first component for laminated glass and the second component for
laminated glass, wherein the interlayer film is the interlayer film
for laminated glass described above.
Effect of the Invention
The interlayer film for laminated glass according to the present
invention includes the first layer and the second layer laminated
on the first surface of the first layer, and further, the first
layer includes the polyvinyl acetate resin and the plasticizer, and
thus, the sound insulation property of the laminated glass using
the interlayer film for laminated glass according to the present
invention can be improved.
BRIEF DESCRIPTION OF DRAWINGS
FIG. 1 is a partially cross-sectional view schematically
illustrating an interlayer film for laminated glass according to
one embodiment of the present invention.
FIG. 2 is a partially cross-sectional view schematically
illustrating an example of a laminated glass using the interlayer
film for laminated glass illustrated in FIG. 1.
MODE(S) FOR CARRYING OUT THE INVENTION
Hereinafter, the present invention will be clarified by describing
specific embodiments and examples of the present invention with
reference to the drawings.
In FIG. 1, an interlayer film for laminated glass according to one
embodiment of the present invention is schematically illustrated as
a partially cross-sectional view.
The interlayer film 1 illustrated in FIG. 1 is a multi-layer
interlayer film. The interlayer film 1 is used for obtaining a
laminated glass. The interlayer film 1 is an interlayer film for
laminated glass. The interlayer film 1 includes a first layer 2, a
second layer 3 laminated on a first surface 2a of the first layer
2, and a third layer 4 laminated on a second surface 2b opposite to
the first surface 2a of the first layer 2. The first layer 2 is an
intermediate layer and mainly functions as a sound insulation
layer. The second and the third layers 3, 4 are protection layers
and, in this embodiment, surface layers. The first layer 2 is
sandwiched between the second and the third layers 3, 4. The
interlayer film 1, therefore, has a multi-layer structure in which
the second layer 3, the first layer 2, and the third layer 4 are
laminated in this order.
Compositions of the second layer 3 and the third layer 4 may be the
same as or different from each other. When the polyvinyl acetal
resin is included in the second and the third layers 3, 4, adhesion
force between the second and the third layers 3, 4 and the
component for laminated glass is sufficiently high.
Main characteristics of this embodiment is that the interlayer film
1 includes the first layer 2 and the second layer 3 laminated on
the first surface 2a of the first layer 2 and further the first
layer 2 includes the polyvinyl acetate resin and the plasticizer.
By this structure, the sound insulation property of the laminated
glass using the interlayer film 1 can be improved. Further, the
sound insulation property of the laminated glass using the
interlayer film 1 in the high frequency range can also be improved.
Particularly, the sound insulation property in a high frequency
range exceeding 3 kHz can be effectively improved.
In the interlayer film 1, the second and the third layers 3, 4 are
laminated one by one on both sides of the first layer 2. The second
layer should be laminated on at least one surface of the first
layer. The second layer may be laminated only on the first surface
of the first layer and the third layer may not be laminated on the
second surface of the first layer. It is desirable, however, that
the second layer is laminated on the first surface of the first
layer and the third layer is laminated on the second surface of the
first layer. Penetration resistance of the laminated glass using
the interlayer film becomes further higher by laminating the third
layer on the second surface of the first layer.
From the viewpoint of further improvement of the sound insulation
property of the laminated glass, the polyvinyl acetate resin and
the plasticizer included in the first layer are preferably a
polyvinyl acetate resin and a plasticizer having a cloud point of
80.degree. C. or less that is measured by using a solution in which
8 parts by weight of the polyvinyl acetate resin is dissolved in
100 parts by weight of the plasticizer. Although the lower limit of
the cloud point is not particularly limited, the cloud point may be
60.degree. C. or more and may be 70.degree. C. or more.
The cloud point described above is a cloud point measured according
to JIS K2266 "Testing Methods for Pour Point of Crude Oil and
Petroleum Products and Cloud Point of Petroleum Products".
Specifically, the cloud point measured by using the polyvinyl
acetate resin and the plasticizer means a temperature in which,
when 3.5 g (100 parts by weight) of the plasticizer and 0.28 g (8
parts by weight) of the polyvinyl acetate resin are provided; 3.5 g
(100 parts by weight) of the plasticizer and 0.28 g (8 parts by
weight) of the polyvinyl acetate are mixed in a test tube (diameter
2 cm); a solution made by dissolving the polyvinyl acetate resin in
the plasticizer is heated to 150.degree. C.; and thereafter, when a
temperature of the solution is lowered to -15.degree. C. by
allowing the test tube to stand under an atmosphere of -20.degree.
C. or the temperature of the solution is lowered to a pour point
temperature of the plasticizer by allowing the test tube to stand
under an atmosphere of -196.degree. C., a part of the solution
starts to cloud (a first determination method of the cloud point).
A lower cloud point indicates higher compatibility of the polyvinyl
acetate resin and the plasticizer. When the part of the solution
starts to cloud by lowering the temperature of the solution to
-15.degree. C. by allowing the test tube to stand under the
atmosphere of -20.degree. C., the test tube is allowed to stand not
under the atmosphere of -196.degree. C. but under the atmosphere of
-20.degree. C.
The part of the solution may not cloud even when the temperature of
the solution is lowered to the pour point temperature of the
plasticizer. In this case, the cloud point is determined to be a
temperature far below than 0.degree. C. This case means that the
compatibility of the polyvinyl acetate resin and the plasticizer is
significantly high.
Consequently, when the cloud point is evaluated, 8 parts by weight
of the polyvinyl acetate resin included in the first layer and 100
parts by weight of the plasticizer included in the first layer are
provided, and thereafter, the solution made by dissolving 8 parts
by weight of the polyvinyl acetate resin in 100 parts by weight of
the plasticizer is used.
Examples of methods for measuring the temperature at which a part
of the solution starts to cloud (cloud point) include a method for
visually observing appearance of the solution, a method for
measuring haze of the solution with a haze-meter, and a method in
which several steps of boundary samples with respect to cloudiness
is previously prepared and cloudiness is determined in comparison
with the boundary samples. Among these methods, the method for
visually observing the appearance of the solution is preferable.
When the haze of the solution is measured with the haze-meter, a
temperature at which a haze is 10% or more is determined to be the
cloud point.
The cloud point measured by using the polyvinyl acetate resin and
the plasticizer may also be determined in the manner that, when 3.5
g (100 parts by weight) of the plasticizer and 0.28 g (8 parts by
weight) of the polyvinyl acetate resin are provided; 3.5 g (100
parts by weight) of the plasticizer and 0.28 g (8 parts by weight)
of the polyvinyl acetate are mixed in a test tube (diameter 2 cm);
a solution made by dissolving the polyvinyl acetate resin in the
plasticizer is heated to 150.degree. C.; then the test tube is
allowed to stand for 1 hour in a constant temperature room of a
predetermined temperature; and thereafter, when a haze of the
solution in the test tube is measured with the haze-meter with the
temperature of the constant temperature room being maintained, the
haze is 10% or more or not (a second determination method of the
cloud point). For example, a temperature at which a haze of 10% or
more is indicated may be measured by allowing the test tube to
stand for 1 hour in the constant temperature room of 80.degree. C.,
and thereafter, measuring the haze of the solution in the test tube
with the haze-meter with the temperature of the constant
temperature room being maintained. The haze is preferably less than
10% when the haze of the solution in the test tube is measured
using a haze-meter with the temperature of the constant temperature
room being maintained after the test tube is allowed to stand for 1
hour in the constant temperature room of 80.degree. C.
In the present invention, the cloud point may be determined by the
first method for determining the cloud point or may be determined
by the second method for determining the cloud point. The cloud
point is preferably determined by the first method for determining
the cloud point. In order to specify the cloud point with further
accuracy, the second method for determining the cloud point can be
employed.
Hereinafter, details of the first, the second, and the third layers
configuring the interlayer film for laminated glass and details of
each component included in the first, the second, and the third
layers will be described.
(Thermoplastic Resin)
The first layer includes the polyvinyl acetate resin as a
thermoplastic resin. The polyvinyl acetate resin in the first layer
(hereinafter, may be referred to as a "polyvinyl acetate resin (1))
is not particularly limited. The polyvinyl acetate resin (1) is a
thermoplastic resin. The polyvinyl acetate resin (1) can be used
singly or in combination of two or more.
The polyvinyl acetate resin (1) can be obtained by polymerizing a
polymerizable composition including vinyl acetate. The polyvinyl
acetate resin (1) includes modified polyvinyl acetate resins.
Further, the polyvinyl acetate resin (1) includes a copolymer of
vinyl acetate and a polymerizable compound other than vinyl acetate
(copolymer component). The polymerizable composition may include a
polymerizable compound other than vinyl acetate. As the
polymerizable compound, the polymerizable composition preferably
includes vinyl acetate as a main component. When the polyvinyl
acetate is a copolymer of vinyl acetate and the polymerizable
compounds other than vinyl acetate, a ratio of a skeleton derived
from vinyl acetate is preferably 50 mol % or more, more preferably
60 mol % or more, further preferably 70 mol % or more, particularly
preferably 80 mol % or more, and most preferably 90 mol % or more
in 100 mol % of the total skeleton of the copolymer (the polyvinyl
acetate). Examples of the polymerizable compound other than vinyl
acetate include a (meth)acrylic compound, a styrene compound, and
an isoprene compound.
A polymerization degree of the polyvinyl acetate resin (1) is
preferably 1000 or more, preferably 20000 or less, more preferably
15000 or less, and further preferably 5000 or less. When the
polymerization degree is the lower limit or more, the interlayer
film can further easily be obtained by extrusion molding. When the
polymerization degree is the upper limit or lower, production
efficiency of the interlayer film becomes further higher. From the
viewpoint of increase in productivity, the polymerization degree of
the polyvinyl acetate resin (1) is more preferably 1500 or more and
particularly preferably 4000 or less.
The first layer preferably includes the polyvinyl acetal resin
(hereinafter may be referred to as a polyvinyl acetal resin (1)).
When the first layer includes the polyvinyl acetal resin (1),
production efficiency of the interlayer film for laminated glass
becomes higher. The polyvinyl acetal resin (1) is preferably a
polyvinyl acetal resin having an acetylation degree of less than 8
mol % (hereinafter also referred to as a "polyvinyl acetal resin
A") or a polyvinyl acetal resin having an acetylation degree of 8
mol % or more (hereinafter also referred to as a "polyvinyl acetal
resin B").
The acetylation degree a of the polyvinyl acetal resin A is less
than 8 mol %, preferably 7.5 mol % or less, preferably 7 mol % or
less, preferably 6 mol % or less, preferably 5 mol % or less,
preferably 0.1 mol % or more, preferably 0.5 mol % or more,
preferably 0.8 mol % or more, preferably 1 mol % or more,
preferably 2 mol % or more, preferably 3 mol % or more, and
preferably 4 mol % or more. When the acetylation degree a is the
upper limit or less and the lower limit or more, compatibility
between the polyvinyl acetal resin A and the plasticizer becomes
further higher, and thus, the sound insulation property of the
laminated glass can be further improved.
The lower limit of the acetalization degree a of the polyvinyl
acetal resin A is preferably 68 mol %, more preferably 70 mol %,
further preferably 71 mol %, and particularly preferably 72 mol %,
and the upper limit thereof is preferably 85 mol %, more preferably
83 mol %, further preferably 81 mol %, and particularly preferably
79 mol %. When the acetalization degree a is the lower limit or
more, the sound insulation property of the laminated glass can be
further improved. When the acetalization degree a is the upper
limit or less, reaction time required for producing the polyvinyl
acetal resin can be shortened.
A hydroxyl group content a of the polyvinyl acetal resin A is
preferably 30 mol % or less, preferably 27.5 mol % or less,
preferably 27 mol % or less, preferably 26 mol % or less,
preferably 25 mol % or less, preferably 24 mol % or less,
preferably 23 mol % or less, preferably 16 mol % or more,
preferably 18 mol % or more, preferably 19 mol % or more, and
preferably 20 mol % or more. When the hydroxyl group content a is
the upper limit or less, the sound insulation property of the
laminated glass can be further improved. When the hydroxyl group
content a is the lower limit or more, adhesion force of the
interlayer film can be further increased.
The polyvinyl acetal resin A is preferably a polyvinyl butyral
resin.
The acetylation degree b of the polyvinyl acetal resin B is 8 mol %
or more, preferably 9 mol % or more, preferably 10 mol % or more,
preferably 11 mol % or more, preferably 12 mol % or more,
preferably 30 mol % or less, preferably 28 mol % or less,
preferably 26 mol % or less, preferably 24 mol % or less,
preferably 20 mol % or less, and preferably 19.5 mol % or less.
When the acetylation degree b is the lower limit or more, the sound
insulation property of the laminated glass can be further improved.
When the acetylation degree b is the upper limit or less, the
reaction time required for producing the polyvinyl acetal resin B
can be shortened. Among them, the acetylation degree b of the
polyvinyl acetal resin B is preferably less than 20 mol % because
the reaction time required for producing the polyvinyl acetal resin
B can be further shortened.
The lower limit of the acetalization degree b of the polyvinyl
acetal resin B is preferably 50 mol %, more preferably 52.5 mol %,
further preferably 54 mol %, and particularly preferably 60 mol %,
and the upper limit thereof is preferably 80 mol %, more preferably
77 mol %, further preferably 74 mol %, and particularly preferably
71 mol %. When the acetalization degree b is the lower limit or
more, the sound insulation property of the laminated glass can be
further improved. When the acetalization degree b is the upper
limit or less, the reaction time required for producing the
polyvinyl acetal resin B can be shortened.
A hydroxyl group content b of the polyvinyl acetal resin B is
preferably 30 mol % or less, preferably 27.5 mol % or less,
preferably 27 mol % or less, preferably 26 mol % or less,
preferably 25 mol % or less, preferably 18 mol % or more,
preferably 20 mol % or more, preferably 22 mol % or more, and
preferably 23 mol % or more. When the hydroxyl group content b is
the upper limit or less, the sound insulation property of the
laminated glass can be further improved. When the hydroxyl group
content b is the lower limit or more, the adhesion force of the
interlayer film can be further increased.
The polyvinyl acetal resin B is preferably a polyvinyl butyral
resin.
The polyvinyl acetal resin A and the polyvinyl acetal resin B are
preferably obtained by acetalizing a polyvinyl alcohol resin having
an average polymerization degree exceeding 3000 with an aldehyde.
The aldehyde is preferably an aldehyde having a carbon number of 1
to 10 and more preferably an aldehyde having a carbon number of 4
or 5. A lower limit of the average polymerization degree of the
polyvinyl alcohol resin is preferably 3010, preferably 3050,
preferably 3500, preferably 3600, preferably 4000, and preferably
4050, and an upper limit thereof is preferably 7000, preferably
6000, preferably 5000, preferably 4900, and preferably 4500. The
polyvinyl acetal resins A, B in the first layer are particularly
preferably obtained by acetalizing a polyvinyl alcohol resin having
an average polymerization degree exceeding 3000 and less than 4000.
The average polymerization degree of the polyvinyl alcohol resin
used for obtaining the polyvinyl acetal resins A, B in the first
layer is preferably 3010 or more, more preferably 3020 or more,
preferably 4000 or less, more preferably less than 4000, further
preferably 3800 or less, particularly preferably 3600 or less, and
most preferably 3500 or less because bubble generation and bubble
growth in the laminated glass is further reduced; the sound
insulation property is sufficiently improved; and the interlayer
film can be easily formed.
When the first layer includes a polyvinyl acetate resin (1) and a
polyvinyl acetal resin (1), a ratio of the polyvinyl acetate resin
(1) in 100% by weight of the total of the polyvinyl acetate resin
(1) and the polyvinyl acetal resin (1) is preferably 1% by weight
or more, more preferably 10% by weight or more, further preferably
20% by weight or more, particularly preferably 50% by weight more,
preferably 99% by weight or less, more preferably 90% by weight or
less, and further preferably 80% by weight or less. When the ratio
is the upper limit or less, the production efficiency of the
interlayer film for laminated glass becomes further higher. When
the ratio is the lower limit or more, the sound insulation property
of the laminated glass can be further improved.
The second layer preferably includes a thermoplastic resin and more
preferably includes a polyvinyl acetal resin (hereinafter, may be
referred to as a polyvinyl acetal resin (2)). The third layer
preferably includes a thermoplastic resin and more preferably
includes a polyvinyl acetal resin (hereinafter, may be referred to
as a polyvinyl acetal resin (3)). When the second and the third
layers include polyvinyl acetal resins (2), (3), adhesion force
between the second and the third layers and the component for
laminated glass is sufficiently high. In the second and the third
layers, each of the thermoplastic resin may be used singly or in
combination of two or more. Each of the polyvinyl acetal resin (2),
(3) may be used singly or in combination of two or more. The
thermoplastic resins used in the second and the third layers are
not particularly limited. The polyvinyl acetal resins (2), (3) used
in the second and the third layers are not particularly
limited.
Examples of the thermoplastic resin include a polyvinyl acetal
resin, an ethylene-vinyl acetate copolymer resin, an
ethylene-acrylic copolymer resin, a polyurethane resin and a
polyvinyl alcohol resin.
The acetylation degree of the polyvinyl acetal resin (2), (3) is
preferably 0 mol % or more, more preferably 0.1 mol % or more,
further preferably 0.5 mol % or more, preferably 30 mol % or less,
more preferably 20 mol % or less, much more preferably 15 mol % or
less, further preferably 10 mol % or less, particularly preferably
5 mol % or less, and most preferably 3 mol % or less. When the
acetylation degree is the upper limit or less, the penetration
resistance of the interlayer film and the laminated glass are
enhanced. When the acetylation degree is the upper limit or less,
the bleed-out of the plasticizer can be reduced.
When the acetylation degree of the polyvinyl acetal resins in the
polyvinyl acetal resins (2), (3) is 3 mol % or less, mechanical
properties of the interlayer film are further enhanced. As a
result, the penetration resistance of the laminated glass is
further enhanced.
The acetylation degree is obtained as described below. The amount
of ethylene group having the acetal group bonded thereto and the
amount of ethylene group having the hydroxy group bonded thereto
are subtracted from the total amount of ethylene groups in the main
chain. The obtained value is divided by the total amount of
ethylene groups in the main chain to obtain a molar fraction. The
acetylation degree is the molar fraction expressed in percentage.
The amount of the ethylene group to which the acetal group or the
hydroxy group bonds can be determined, for example, according to
JIS K6728 "Testing methods for polyvinyl butyral".
The polyvinyl acetal resin (2), (3) can be produced, for example,
by acetalizing a polyvinyl alcohol with an aldehyde. The polyvinyl
alcohol can be obtained by, for example, saponifying polyvinyl
acetate.
The average polymerization degree of the polyvinyl alcohol for
obtaining the polyvinyl acetal resins (2), (3) is preferably 200 or
more, more preferably 500 or more, further preferably 1600 or more,
particularly preferably 2600 or more, most preferably 2700 or more,
preferably 5000 or less, more preferably 4000 or less, and further
preferably 3500 or less. When the average polymerization degree is
the lower limit or more, the penetration resistance of the
laminated glass is further enhanced. When the average
polymerization degree is the upper limit or less, molding of the
interlayer film is easy.
The average polymerization degree of the polyvinyl alcohol is
determined by a method according to JIS K6726 "Testing methods for
polyvinyl alcohol".
A carbon number of an acetal group included in the polyvinyl acetal
resin is not particularly limited. An aldehyde used at the time of
production of the polyvinyl acetal resin is not particularly
limited. The carbon number of the acetal group included in the
polyvinyl acetal resin is preferably 3 to 5, and more preferably 3
or 4 from the viewpoint of increase in productivity.
The aldehyde is not particularly limited. As the aldehyde,
generally, an aldehyde having a carbon number of 1 to 10 is
preferably used. Examples of the aldehyde having the carbon number
of 1 to 10 include propionaldehyde, n-butyraldehyde,
isobutyraldehyde, n-valeraldehyde, 2-ethylbutyraldehyde,
n-hexylaldehyde, n-octylaldehyde, n-nonylaldehyde, n-decylaldehyde,
formaldehyde, acetaldehyde, and benzaldehyde. Among them,
propionaldehyde, n-butyraldehyde, isobutyraldehyde, n-hexylaldehyde
or n-valeraldehyde is preferable; propionaldehyde, n-butyraldehyde,
or isobutyraldehyde is more preferable; and n-butyraldehyde is
further preferable. The aldehyde can be used singly or in
combination of two or more.
Each of the polyvinyl acetal resins (2), (3) is preferably a
polyvinyl butyral resin. The interlayer film for laminated glass
according to the present invention preferably includes the
polyvinyl butyral resin as each of the polyvinyl acetal resins (2),
(3) included in the second and the third layers. Synthesis of the
polyvinyl butyral resin is easy. By the use of the polyvinyl
butyral resin, adhesion force of the interlayer film to the
component for laminated glass is further adequately generated.
Light resistance and weather resistance are also further
improved.
A hydroxyl group content (an amount of the hydroxy group) in each
of the polyvinyl acetal resins (2), (3) is preferably 20 mol % or
more, more preferably 25 mol % or more, further preferably 30 mol %
or more, preferably 50 mol % or less, more preferably 45 mol % or
less, further preferably 40 mol % or less, and particularly
preferably 35 mol % or less. When the hydroxyl group content is the
lower limit or more, the penetration resistance of the laminated
glass is further enhanced. When the hydroxyl group content is the
upper limit or less, the bleed-out of the plasticizer is difficult
to occur. In addition, the interlayer film is more flexible, and
therefore, handling of the interlayer film becomes easy.
The hydroxyl group content of the polyvinyl acetal resins (2), (3)
is a value expressed in percentage (mol %) of a molar fraction
determined by dividing an amount of the ethylene group to which the
hydroxy group bonds by an amount of the total ethylene group in the
main chain.
An acetalization degree (a butyralization degree in the case of the
polyvinyl butyral resin) of each of the polyvinyl acetal resins
(2), (3) is preferably 55 mol % or more, more preferably 60 mol %
or more, further preferably mol % or more, preferably 85 mol % or
less, more preferably 75 mol % or less, and further preferably 70
mol % or less. When the acetalization degree is the lower limit or
more, compatibility between the polyvinyl acetal resins (2), (3)
and the plasticizer is improved. When the acetalization degree is
the upper limit or less, the reaction time required for producing
the polyvinyl acetal resin is shortened.
The acetalization degree is a value expressed in percentage (mol %)
of a molar fraction determined by dividing an amount of the
ethylene group to which the acetal group bonds by an amount of the
total ethylene group in the main chain.
The acetalization degree (the butyralization degree) and the
acetylation degree of the polyvinyl acetal resin (polyvinyl butyral
resin) can be calculated from the result of measurement by a method
according to JIS K6728 "Testing methods for polyvinyl butyral" or
ASTM D1396-92. The measurement is preferably carried out by the
method according to ASTM D1396-92.
From the viewpoint of further improvement of the sound insulation
property of the laminated glass, it is preferable that the
acetylation degree of the polyvinyl acetal resin in the second
layer is 15 mol % or less and the hydroxyl group content thereof is
20 mol % or less. From the viewpoint of further improvement of the
sound insulation property of the laminated glass, it is preferable
that the acetylation degree of the polyvinyl acetal resin in the
third layer is 15 mol % or less and the hydroxyl group content
thereof is 20 mol % or less.
(Plasticizer)
The first layer includes a plasticizer (hereinafter may be referred
to as a plasticizer (1)). The second layer preferably includes the
plasticizer (hereinafter may be referred to as a plasticizer (2)).
The third layer preferably includes the plasticizer (hereinafter
may be referred to as a plasticizer (3)). Each of the plasticizers
(1), (2), (3) may be used singly or in combination of two or
more.
Examples of the plasticizers (1), (2), (3) include organic ester
plasticizers such as monobasic organic acid esters and polybasic
organic acid esters and phosphoric acid plasticizers such as
organic phosphate plasticizers and organic phosphite plasticizers.
Among them, the organic ester plasticizers are preferable. The
plasticizers (1), (2), (3) are preferably liquid plasticizers.
The monobasic organic acid ester is not particularly limited, and
examples of the monobasic organic acid ester include a glycol ester
obtained by reacting a glycol with a monobasic organic acid and an
ester made of triethylene glycol or tripropylene glycol and a
monobasic organic acid. Examples of the glycol include triethylene
glycol, tetraethylene glycol, and tripropylene glycol. Examples of
the monobasic organic acid include butyric acid, isobutyric acid,
caproic acid, 2-ethylbutyric acid, heptylic acid, n-octylic acid,
2-ethylhexanoic acid, n-nonylic acid and decylic acid.
The polybasic organic acid ester is not particularly limited and
examples of the polybasic organic acid ester include ester
compounds of polybasic organic acids and alcohols having a linear
or a branched structure having a carbon number of 4 to 8. Examples
of the polybasic organic acid include adipic acid, sebacic acid,
and azelaic acid.
The organic ester plasticizer is not particularly limited and
examples of the plasticizer include triethylene glycol
di-2-ethylbutyrate, triethylene glycol di-2-ethylhexanoate,
triethylene glycol dicaprylate, triethylene glycol di-n-octanoate,
triethylene glycol di-n-heptanoate, tetraethylene glycol
di-n-heptanoate, dibutyl sebacate, dioctyl azelate, dibutylcarbitol
adipate, ethylene glycol di-2-ethylbutyrate, 1,3-propylene glycol
di-2-ethylbutyrate, 1,4-butylene glycol di-2-ethylbutyrate,
diethylene glycol di-2-ethylbutyrate, diethylene glycol
di-2-ethylhexanoate, dipropylene glycol di-2-ethylbutyrate,
triethylene glycol di-2-ethylpentanoate, tetraethylene glycol
di-2-ethylbutyrate, diethylene glycol dicaprylate, dibutyl adipate,
dihexyl adipate, dioctyl adipate, hexylcyclohexyl adipate, a
mixture of heptyl adipate and nonyl adipate, diisononyl adipate,
diisodecyl adipate, heptylnonyl adipate, dibutyl sebacate,
oil-modified sebacic alkyds, and a mixture of adipate esters and
phosphoric acid esters. Other ester plasticizers other than these
plasticizers may be used.
The organic phosphoric acid plasticizers are not particularly
limited, and examples of the organic phosphoric acid esters include
tributoxyethyl phosphate, isodecylphenyl phosphate, and
tri-isopropyl phosphate.
From the viewpoint of further improvement of the sound insulation
property of the laminated glass, the plasticizer (1) in the first
layer is preferably a diester plasticizer represented by Formula
(1). From the viewpoint of further improvement of the sound
insulation property of the laminated glass, the plasticizers (2),
(3) in the second and the third layers are preferably a diester
plasticizer represented by Formula (1).
##STR00001##
In Formula (1), R1 and R2 each represents an organic group having a
carbon number of 5 to 10; R3 represents an ethylene group, an
isopropylene group or a n-propylene group, and p represents an
integer of 3 to 10.
The plasticizer (1) preferably includes at least one of dibutyl
adipate, triethylene glycol di-n-butanoate (3 GB), triethylene
glycol di-n-propanoate (3GE), triethylene glycol
di-2-ethylhexanoate (3GO), and triethylene glycol
di-2-ethylbutyrate (3GH), more preferably includes at least one of
dibutyl adipate, triethylene glycol di-2-ethylhexanoate (3GO), and
triethylene glycol di-2-ethylbutyrate (3GH), further preferably
includes at least one of triethylene glycol di-2-ethylhexanoate
(3GO) and triethylene glycol di-2-ethylbutyrate (3GH), and
particularly preferably includes triethylene glycol
di-2-ethylhexanoate (3GO).
From the viewpoint of further improvement of the sound insulation
property of the laminated glass, the polyvinyl acetate resin and
the plasticizer (1) in the first layer are preferably used in a
combination to show a cloud point of 80.degree. C. or less that is
measured by using a solution in which 8 parts by weight of the
polyvinyl acetate resin is dissolved in 100 parts by weight of the
plasticizer (1).
Each of the plasticizers (2), (3) preferably include at least one
of dibutyl adipate, triethylene glycol di-n-butanoate (3 GB),
triethylene glycol di-n-propanoate (3GE), triethylene glycol
di-2-ethylhexanoate (3GO), and triethylene glycol
di-2-ethylbutyrate (3GH), more preferably includes at least one of
dibutyl adipate, triethylene glycol di-2-ethylhexanoate (3GO), and
triethylene glycol di-2-ethylbutyrate (3GH), further preferably
includes at least one of triethylene glycol di-2-ethylhexanoate
(3GO) and triethylene glycol di-2-ethylbutyrate (3GH), and
particularly preferably includes triethylene glycol
di-2-ethylhexanoate.
In the first layer, a content of the plasticizer (1) to 100 parts
by weight of the polyvinyl acetate resin (1) is preferably 25 parts
by weight or more and preferably 80 parts by weight or less. From
the viewpoint of further improvement of the sound insulation
property of the laminated glass, the content of the plasticizer (1)
to 100 parts by weight of the polyvinyl acetate resin in the first
layer is more preferably 30 parts by weight or more, and more
preferably 70 parts by weight or less, further preferably 60 parts
by weight or less, and particularly preferably 50 parts by weight
or less. In addition, when the content of the plasticizer (1) is
the lower limit or more, the interlayer film has higher flexibility
and easier handling, and further, the penetration resistance of the
laminated glass is further enhanced. When the content of the
plasticizer (1) is the upper limit or less, transparency of the
interlayer film is further improved. From the viewpoint of further
improvement of the production efficiency of the interlayer film,
the content of the plasticizer (1) to 100 parts by weight of the
polyvinyl acetate resin (1) in the first layer is preferably 30
parts by weight or more and preferably 70 parts by weight or
less.
When the first layer includes the polyvinyl acetate (1) and the
polyvinyl acetal resin (1), the content of the plasticizer (1) to
100 parts by weight of the total of the polyvinyl acetate (1) and
the polyvinyl acetal resin (1) is preferably 25 parts by weight,
more preferably 30 parts by weight or more, preferably 80 parts by
weight or less, more preferably 70 parts by weight or less, further
preferably 60 parts by weight or less, and particularly preferably
50 parts by weight or less. When the content of the plasticizer (1)
is the lower limit or more, the interlayer film has higher
flexibility and easier handling, and further, the penetration
resistance of the laminated glass is further enhanced. When the
content of the plasticizer (1) is the upper limit or less,
transparency of the interlayer film is further improved.
In the second layer, a content of the plasticizer (2) to 100 parts
of the polyvinyl acetal resin (2) is preferably 5 parts by weight
or more, more preferably 10 parts by weight or more, further
preferably 15 parts by weight or more, preferably 50 parts by
weight or less, more preferably 45 parts by weight or less, and
further preferably 40 parts by weight or less. In the third layer,
a content of the plasticizer (3) to 100 parts of the polyvinyl
acetal resin (3) is preferably 5 parts by weight or more, more
preferably 10 parts by weight or more, further preferably 15 parts
by weight or more, preferably 50 parts by weight or less, more
preferably 45 parts by weight or less, and further preferably 40
parts by weight or less. When the contents of the plasticizers (2),
(3) are the lower limit or more, flexibility of the interlayer film
is higher and handling of the interlayer film becomes easy. When
the contents of the plasticizers (2), (3) are the upper limit or
less, the penetration resistance of the laminated glass is further
enhanced.
The content of the plasticizer (2) in the second layer to 100 parts
by weight of the polyvinyl acetal resin (2) in the second layer
(hereinafter may be referred to as a content (2)) is preferably
less than the content of the plasticizer (1) in the first layer to
100 parts by weight of the polyvinyl acetate resin (1) in the first
layer (hereinafter may be referred to as a content (1)). The
content of the plasticizer (3) in the third layer to 100 parts by
weight of the polyvinyl acetal resin (3) in the third layer
(hereinafter may be referred to as a content (3)) is preferably
less than the content of the plasticizer (1) in the first layer to
100 parts by weight of the polyvinyl acetate resin (1) in the first
layer (hereinafter may be referred to as a content (1)). When the
contents (2), (3) are less than the content (1), the penetration
resistance of the laminated glass is further enhanced.
Each absolute value of difference between the content (1) and the
content (2) and absolute value of difference between the content
(1) and the content (3) is preferably 5 parts by weight or more,
more preferably 10 parts by weight or more, further preferably 15
parts by weight or more, particularly preferably 20 parts by weight
or more, preferably 40 parts by weight or less, more preferably 35
parts by weight or less, and further preferably 30 parts by weight
or less. When the absolute values of the differences between the
content (1) and each of the contents (2), (3) are the lower limit
or more, the sound insulation property of the laminated glass is
further improved, whereas when the absolute values thereof are the
upper limit or less, the penetration resistance of the laminated
glass is further enhanced.
(Tackifier)
The first layer preferably includes a tackifier. When the first
layer includes the tackifier, adhesion between the first layer to
the second and the third layers is further improved and the
penetration resistance of the laminated glass is further enhanced.
The inventors of the present invention have found that the first
layer includes the tackifier, and thereby, the sound insulation
property of the laminated glass is also improved. The first layer
includes the tackifier, and thereby, the sound insulation property
of the laminated glass in the high frequency range can also be
improved.
Examples of the tackifier include rosin resins, terpene resins, and
petroleum resins. The tackifier may be used singly or in
combination of two or more. The second and the third layers may
include or may not include the tackifier.
From the viewpoint of further improvement of the sound insulation
property of the laminated glass, the tackifier is preferably the
rosin resin.
The rosin resin is a resin made of rosin or a rosin derivative as a
base. Examples of the rosin resin include rosin, acid-modified
rosin, a rosin-containing diol, a rosin ester, a hydrogenated rosin
ester, and a maleic acid-modified rosin ester. An example of the
acid-modified rosin includes acrylic acid-modified rosin.
A content of the tackifier to 100 parts by weight of the polyvinyl
acetate resin (1) in the first layer is preferably 10 parts by
weight or more, more preferably 20 parts by weight or more, further
preferably 25 parts by weight or more, particularly preferably 30
parts by weight or more, most preferably 50 parts by weight or
more, preferably 500 parts by weight or less, more preferably 300
parts by weight or less, further preferably 100 parts by weight or
less, and particularly preferably 90 parts by weight or less. When
the content of the tackifier is the lower limit or more, the sound
insulation property of the laminated glass is further improved.
When the content exceeds the upper limit, the tackifier may become
excessive in order to improve the sound insulation property.
(Other Components)
Each of the first, the second, and the third layers, if necessary,
may include additives such as an ultraviolet absorber, an
antioxidant, a light stabilizer, a flame retardant, an antistatic
agent, a pigment, a dye, an adhesion modifier, a moisture
resistance agent, a fluorescent whitening agent, and an infrared
absorbing agent. These additives may be used singly or in
combination of two or more.
(Interlayer for Laminated Glass)
From the viewpoint of further improvement of the sound insulation
property of the laminated glass, a peak temperature of tan .delta.
of the interlayer film for laminated glass according to the present
invention that appears at the lowest temperature side measured at a
frequency of 1 Hz is preferably 0.degree. C. or less.
From the viewpoint of further improvement of the sound insulation
property of the laminated glass in low temperature, a maximum value
of the tan .delta. at the peak temperature of the tan .delta. that
appears at the lowest temperature side measured at a frequency of 1
Hz is preferably 1.15 or more, and more preferably 1.25 or
more.
From the viewpoint of further improvement of the sound insulation
property of the laminated glass in high temperature, a maximum
value of the tan .delta. at the peak temperature of the tan .delta.
that appears at the highest temperature side measured at a
frequency of 1 Hz is preferably 0.50 or more.
When the peak temperature of the tan .delta. that appears at the
lowest temperature side, the maximum value of the tan .delta. at
the peak temperature of the tan .delta. that appears at the lowest
temperature side, and the maximum value of the tan .delta. at the
peak temperature of the tan .delta. that appears at the highest
temperature side are measured, the measurement is preferably
carried out after the interlayer film for laminated glass is stored
under the condition of 23.degree. C. for 1 month.
A thickness of the first layer is preferably 0.02 mm or more, more
preferably 0.05 mm or more, preferably 1.8 mm or less, and more
preferably 0.5 mm or less. When the thickness of the first layer is
the lower limit or more and the upper limit or less, the thickness
of the interlayer film is not too thick and the sound insulation
property of the laminated glass is further improved.
Each thickness of the second and the third layers is preferably 0.1
mm or more, more preferably 0.2 mm or more, preferably 1 mm or
less, and more preferably 0.5 mm or less. When the thicknesses of
the second and the third layers are the lower limit or more and the
upper limit or less, the thickness of the interlayer film is not
too thick; the sound insulation property of the laminated glass is
further improved; and further the bleed-out of the plasticizer can
be reduced.
A thickness of the interlayer film for laminated glass according to
the present invention is preferably 0.1 mm or more, more preferably
0.25 mm or more, preferably 3 mm or less, and more preferably 1.5
mm or less. When the thickness of the interlayer film is the lower
limit or more, the penetration resistance of the laminated glass is
sufficiently high. When the thickness of the interlayer film is the
upper limit or less, transparency of the interlayer film is further
improved.
A method for producing the interlayer film for laminated glass
according to the present invention is not particularly limited. As
the method for producing the interlayer film, a heretofore known
method can be used. For example, a method in which the polyvinyl
acetate resin or the polyvinyl acetal resin and the plasticizer and
the other formulated components if necessary are kneaded to form
the interlayer film is included. A production method using an
extruder is preferable because the method is suitable for
continuous production.
The kneading method is not particularly limited. Examples of the
kneading method include a method using an extruder, a plastograph,
a kneader, a Banbury mixer or a calendar roll. Among them, the
method using the extruder is preferable because the method is
suitable for the continuous production, and the method using a twin
screw extruder is more preferable. The interlayer film for
laminated glass according to the present invention may be obtained
by separately preparing the first layer and the second and the
third layers, and thereafter, laminating the first layer and the
second and the third layers, or may be obtained by laminating the
first layer and the second and the third layers by
co-extrusion.
Since production efficiency of the interlayer film is excellent,
the same polyvinyl acetal resin is preferably included in the
second and the third layers; the same polyvinyl acetal resin and
the same plasticizer are more preferably included in the second and
the third layers; and the second and the third layers are further
preferably formed by the same resin composition.
(Laminated Glass)
In FIG. 2, an example of the laminated glass using the interlayer
film for laminated glass of an embodiment of the present invention
is illustrated by a cross-sectional view.
A laminated glass 11 illustrated in FIG. 2 includes the interlayer
film 1 and a first and a second components for laminated glass 21,
22. The interlayer film 1 is sandwiched between the first and the
second components for laminated glass 21, 22. The first component
for laminated glass 21 is laminated on a first surface 1a of the
interlayer film 1. The second component for laminated glass 22 is
laminated on a second surface 1b opposite to the first surface 1a
of the interlayer film 1. The first component for laminated glass
21 is laminated on an outer surface 3a of the second layer 3. The
second component for laminated glass 22 is laminated on an outer
surface 4a of the third layer 4.
As described above, the laminated glass according to the present
invention includes the first component for laminated glass, the
second component for laminated glass, and the interlayer film
sandwiched between the first and the second components for
laminated glass, and the interlayer film for laminated glass of the
present invention is used as the interlayer film.
Examples of the first and the second components for laminated glass
(laminated glass configuration components) include a glass plate
and a PET (polyethylene terephthalate) film. The laminated glass
includes not only the laminated glass made by sandwiching the
interlayer film between the two glass plates, but also a laminated
glass made by sandwiching the interlayer film between the glass
plate and the PET film or the like. The laminated glass is a
laminated body including the glass plate, and at least one glass
plate is preferably used in the laminated glass.
Examples of the glass plate include inorganic glass and organic
glass. Examples of the inorganic glass include a float plate glass,
a heat ray absorbing plate glass, a heat-reflecting plate glass, a
polished plate glass, a figured plate glass, a wire plate glass,
and a green glass. The organic glass is synthetic resin glass
substituted for the inorganic glass. Examples of the organic glass
include a polycarbonate plate and a poly(meth)acrylic resin plate.
An example of the poly(meth)acrylic resin plate includes a
polymethyl(meth)acrylate plate.
Although thicknesses of the first and the second components for
laminated glass are not particularly limited, the thicknesses are
preferably in a range of 1 mm to 5 mm. When the component for
laminated glass is a glass plate, a thickness of the glass plate is
preferably in a range of 1 mm to 5 mm. When the component for
laminated glass is a PET film, a thickness of the PET film is
preferably in a range of 0.03 mm to 0.5 mm.
A method for producing the laminated glass is not particularly
limited. For example, the interlayer film is sandwiched between the
first and the second components for laminated glass, and then,
passed through pressure rolls or subjected to decompression suction
in a rubber bag, so that the air remaining between the first and
the second components for laminated glass and the interlayer film
is removed. Thereafter, a laminated body is obtained by
pre-adhering the first and the second components for laminated
glass and the interlayer film at 70.degree. C. to 110.degree. C.
Subsequently, the laminated body is press-bonded under a pressure
of 1 MPa to 1.5 MPa at about 120.degree. C. to 150.degree. C. by
entering into an autoclave or pressing. As described above, the
laminated glass can be obtained.
The laminated glass can be used for automobiles, railway cars,
aircraft, ships, and architectural structures. The laminated glass
can be used for other applications in addition to these
applications. The interlayer film is preferably an interlayer film
for architectural use and automotive use, and more preferably the
interlayer film for automotive use. The laminated glass is
preferably laminated glass for architectural use and automotive
use, and more preferably the laminated glass for automotive use.
The interlayer film and the laminated glass can be used for other
applications in addition to these applications. The interlayer film
and the laminated glass are preferably used in an electric vehicle
using an electric motor and a hybrid electric vehicle using an
internal combustion engine and an electric motor. The laminated
glass can be used for a windshield, a side glass, a rear glass, and
a roof glass of an automobile.
Hereinafter the present invention will be described in detail with
reference to Examples. The present invention, however, is not
limited to these Examples.
In Examples and Comparative Examples, polyvinyl acetate resins a,
b, c, d and polyvinyl acetal resins a, b, c, d, e described below
were used. The butyralization degree (acetalization degree), the
acetylation degree, and the hydroxyl group content of the polyvinyl
acetal resins a, b, c, d, e as polyvinyl butyral resins were
measured by a method according to ASTM D1396-92. When these
properties were measured by JIS K6728 "Testing methods for
polyvinyl butyral", same values to the values determined by the
method according to ASTM D1396-92 were obtained.
Polyvinyl acetate resin a (PVAc (a)): polymerization degree
1700
Polyvinyl acetate resin b (PVAc (b)): polymerization degree
5000
Polyvinyl acetate resin c (PVAc (c)): polymerization degree
10000
Polyvinyl acetate resin d (PVAc (d)): polymerization degree
15000
Polyvinyl acetal resin a (PVB (a)): acetylation degree 12.8 mol %,
butyralization degree 63.5 mol %, hydroxyl group content 23.7 mol
%, n-butyraldehyde was used for acetalization
Polyvinyl acetal resin b (PVB (b)): acetylation degree 1 mol %,
butyralization degree 65.5 mol %, hydroxyl group content 33.5 mol
%, n-butyraldehyde was used for acetalization
Polyvinyl acetal resin c (PVB (c)): acetylation degree 1 mol %,
butyralization degree 68.5 mol %, hydroxyl group content 30.5 mol
%, n-butyraldehyde was used for acetalization
Polyvinyl acetal resin d (PVB (d)): acetylation degree 1 mol %,
butyralization degree 70.3 mol %, hydroxyl group content 28.7 mol
%, n-butyraldehyde was used for acetalization
Polyvinyl acetal resin e (PVB (e)): acetylation degree 1.5 mol %,
butyralization degree 69 mol %, hydroxyl group content 29.5 mol %,
n-butyraldehyde was used for acetalization
The following plasticizers were used in Examples and Comparative
Examples.
Dibutyl adipate (DBA)
Triethylene glycol di-n-butanoate (3 GB)
Triethylene glycol di-n-propanoate (3GE)
Triethylene glycol di-2-ethylhexanoate (3GO)
The following tackifiers were used in Examples and Comparative
Examples.
Rosin resin (KE-311, manufactured by ARAKAWA CHEMICAL INDUSTRIES,
LTD., "PINECRYSTAL KE-311")
Acrylic acid-modified rosin (KE-604, manufactured by ARAKAWA
CHEMICAL INDUSTRIES, LTD., "PINECRYSTAL KE-604")
Rosin-containing diol (D-6011, manufactured by ARAKAWA CHEMICAL
INDUSTRIES, LTD., "PINECRYSTAL D-6011")
Example 1
The polyvinyl acetate resin a (100 parts by weight) and dibutyl
adipate (DBA) as the plasticizer (50 parts by weight) were
sufficiently kneaded with a mixing roll to obtain a composition for
an intermediate layer.
The polyvinyl butyral resin b (100 parts by weight) and dibutyl
adipate (DBA) as the plasticizer (34 parts by weight) were
sufficiently kneaded to obtain a composition for a protection
layer.
The obtained composition for the intermediate layer and composition
for the protection layer were molded by using a co-extruder to
prepare an interlayer film (a thickness of 0.8 mm) having a
laminated structure of protection layer B (a thickness of 0.35
mm)/intermediate layer A (a thickness of 0.1 mm)/protection layer B
(a thickness of 0.35 mm).
The obtained interlayer film (the multi-layer film) was cut to a
width of 30 mm and a length of 320 mm. Subsequently, the interlayer
film was sandwiched between two transparent float glasses (a width
of 25 mm, a length of 305 mm, and a thickness of 2.0 mm) and the
sandwiched interlayer film was maintained in a vacuum laminator at
90.degree. C. for 30 minutes and pressed under vacuum to obtain a
laminated body. In the laminated body, a part of the interlayer
film protruding from the glass was trimmed off to obtain a
laminated glass.
Example 2
The polyvinyl acetate resin a (100 parts by weight), dibutyl
adipate (DBA) as the plasticizer (50 parts by weight), and the
rosin resin (KE-311, manufactured by ARAKAWA CHEMICAL INDUSTRIES,
LTD., "PINECRYSTAL KE-311") as a tackifier (30 parts by weight)
were sufficiently kneaded with the mixing roll to obtain a
composition for an intermediate layer.
An interlayer film and a laminated glass were obtained in a similar
manner to Example 1 except that an intermediate layer A is prepared
by using the obtained composition for the intermediate layer and a
type and a content of the polyvinyl butyral resin and a content of
the plasticizer used for a protection layer B were set as shown in
Table 1.
Examples 3 to 12
interlayer films and laminated glasses were obtained in a similar
manner to Example 1 except that types and contents of the polyvinyl
acetate resins and types and contents of the plasticizers used in
the intermediate layers and types and contents of the polyvinyl
butyral resins and types and contents of the plasticizers used for
protection layers B were set as shown in Table 1 and 2. The
tackifier was not used in Examples 3 to 12.
Examples 13 and 14
interlayer films and laminated glasses were obtained in a similar
manner to Example 1 except that types and contents of the
tackifiers used in the intermediate layer were set as shown in
Table 2.
Comparative Example 1
An interlayer film and a laminated glass were obtained in a similar
manner to Example 1 except that a type and a content of the
polyvinyl butyral resin and a type and a content of the plasticizer
used for an intermediate layer A and a protection layer B were set
as shown in Table 1. In Comparative Example 1, triethylene glycol
di-2-ethylhexanoate (3GO) was used as the plasticizer. The
tackifier was not used in Comparative Example 1.
(Evaluation)
(1) Cloud Point Measured Using Polyvinyl Acetate Resin or Polyvinyl
Acetal Resin and Plasticizer Included in Intermediate Layer
(1-1) Cloud Point Measured by the First Method for Determining
Cloud Point
Each plasticizer used in the intermediate layer of 3.5 g (100 parts
by weight) and each polyvinyl acetate resin or polyvinyl acetal
resin used in the intermediate layer of 0.28 g (8 parts by weight)
were provided. The plasticizer of 3.5 g (100 parts by weight) and
the polyvinyl acetate resin or the polyvinyl acetal resin of 0.28 g
(8 parts by weight) were mixed in a test tube (a diameter of 2 cm)
to obtain a solution in which the polyvinyl acetate resin or the
polyvinyl acetal resin was dissolved in the plasticizer. After the
solution in the test tube was heated to 150.degree. C., the test
tube was allowed to stand under an atmosphere of -20.degree. C. to
lower a temperature of the solution to -15.degree. C. At this time,
a temperature at which a part of the solution started to generate
cloudiness was visually observed, and the temperature was
determined to be the cloud point.
With respect to the solution in which the cloud point did not
appear even at -15.degree. C., the solution was cooled to the pour
point of the plasticizer under an atmosphere of -196.degree. C.
using liquid nitrogen to lower the temperature. At this time, a
temperature at which a part of the solution started to generate
cloudiness was visually observed, and the temperature was
determined to be the cloud point. In Tables 1 and 2 shown below,
the cloud point was measured by the first method for determining
the cloud point.
(1-2) Cloud Point Measured by the Second Method for Determining
Cloud Point
Each plasticizer used in the intermediate layer of 3.5 g (100 parts
by weight) and each polyvinyl acetate resin or polyvinyl acetal
resin used in the intermediate layer of 0.28 g (8 parts by weight)
were provided. The plasticizer of 3.5 g (100 parts by weight) and
the polyvinyl acetate resin or the polyvinyl acetal resin of 0.28 g
(8 parts by weight) were mixed in a test tube (a diameter of 2 cm)
to obtain a solution in which the polyvinyl acetate resin or the
polyvinyl acetal resin was dissolved in the plasticizer. The
solution in the test tube was heated to 150.degree. C. and the test
tube was allowed to stand for 1 hour in constant temperature rooms
of 5.degree. C., 0.degree. C., and -5.degree. C., and thereafter, a
haze of the solution in the test tube was measured with a
haze-meter with the temperatures of the constant temperature rooms
being maintained. A maximum temperature at which the haze is 10% or
more was determined to be the cloud point. The haze was measured
using the haze-meter (manufactured by Tokyo Denshoku Co., Ltd.,
"TC-HIIIDPK") according to JIS K6714.
As a result, in Examples 1 to 14 and Comparative Example 1, even
after the test tube was allowed to stand for 1 hour in the constant
temperature room of 80.degree. C., the solution did not show a haze
of 10% or more.
(2) Peak Temperature at Lower Temperature Side, Maximum Value of
Peak of Tan .delta. at Lower Temperature Side, and Maximum Value of
Peak of Tan .delta. at Higher Temperature Side
After the obtained interlayer film was stored for 1 month under the
condition of 23.degree. C., a peak temperature of the tan .delta.
that appears at the lowest temperature side, a maximum value of tan
.delta. at the peak temperature of the tan .delta. that appears at
the lowest temperature side, and a maximum value of tan .delta. at
the peak temperature of the tan .delta. that appears at the highest
temperature side were measured by cutting out the interlayer film
in a circle shape having a diameter of 8 mm and measuring
temperature variance of dynamic viscoelasticity at a temperature
rising rate of 5.degree. C./minute under conditions of an amount of
distortion of 1.0% and a frequency of 1 Hz by a shearing method
using a viscoelasticity measuring apparatus (manufactured by
Rheometrics Co., "ARES").
(3) Loss Factor
The obtained laminated glass was stored for 1 month under the
condition of 20.degree. C. For the laminated glass stored for 1
month under the condition of 20.degree. C., a loss factor was
measured under conditions of 20.degree. C. by a central exciting
method using a measurement apparatus "SA-01" (manufactured by RION
Co., Ltd.). A loss factor (loss factor at 20.degree. C.) in a
fourth mode (near 3150 Hz) at a resonance frequency of the obtained
loss factor was evaluated.
For the laminated glass stored for 1 month under the condition of
20.degree. C., a loss factor was also measured under conditions of
30.degree. C. by the central exciting method using the measurement
apparatus "SA-01" (manufactured by RION Co., Ltd.). A loss factor
(loss factor at 30.degree. C.) in a sixth mode (near 6300 Hz) at a
resonance frequency of the obtained loss factor was evaluated.
The results are shown in Table 1 and 2.
TABLE-US-00001 TABLE 1 Ex. 1 Ex. 2 Ex. 3 Ex. 4 Ex. 5 Ex. 6 Ex. 7
Intermediate Resin Type PVAc(a) PVAc(a) PVAc(a) PVAc(a) PVAc(a)
PVAc(a) PV- Ac(a) layer A Content 100 100 100 100 100 100 100
(parts by weight) Type of plasticizer DBA DBA 3GB 3GE DBA DBA DBA
Content of plasticizer 50 50 50 50 50 50 50 (parts by weight)
Tackifier Type -- KE-311 -- -- -- -- -- Amount -- 30 -- -- -- -- --
(parts by weight) Protection Resin Type PVB(b) PVB(b) PVB(c) PVB(c)
PVB(c) PVB(d) PVB(e) layer B Butyralization 65.5 65.5 68.5 68.5
68.5 70.3 69 degree (mol %) Acetylation 1 1 1 1 1 1 1.5 degree (mol
%) Content 100 100 100 100 100 100 100 (parts by weight) Type of
plasticizer DBA DBA 3GB 3GE DBA DBA DBA Content of plasticizer 34
33 33 33 35 36 36.5 (parts by weight) Film configuration B/A/B
B/A/B B/A/B B/A/B B/A/B B/A/B B/A/B Cloud point measured using
resin and 75 75 76 72 75 75 75 plasticizer (.degree. C.) Peak
temperature of tan .delta. at -2.2 -1.4 -2.5 -2.9 -3.1 -2.4 -3.6
lower temperature side (.degree. C.) Maximum value of peak of tan
.delta. at 1.52 1.81 1.64 1.7 1.67 1.63 1.64 lower temperature side
Maximum value of peak of tan .delta. at 0.51 0.5 0.52 0.54 0.51 0.5
0.52 higher temperature side Loss factor at 20.degree. C. near 3150
Hz 0.54 0.69 0.55 0.56 0.53 0.51 0.52 Loss factor at 30.degree. C.
near 6300 Hz 0.17 0.23 0.18 0.18 0.17 0.16 0.17
TABLE-US-00002 TABLE 2 Comp. Ex. 8 Ex. 9 Ex. 10 Ex. 11 Ex. 12 Ex.
13 Ex. 14 Ex. 1 Intermediate Resin Type PVAc(b) PVAc(c) PVAc(d)
PVAc(c) PVAc(c) PVAc(a) PV- Ac(a) PVB(a) layer A Content 100 100
100 100 100 100 100 100 (parts by weight) Type of plasticizer DBA
DBA DBA DBA DBA DBA DBA 3GO Content of plasticizer 50 50 50 30 70
50 50 60 (Parts by weight) Tackifier Type -- -- -- -- -- KE-604
D-6011 -- Amount -- -- -- -- -- 30 30 -- (parts by weight)
Protection Resin Type PVB(c) PVB(c) PVB(c) PVB(c) PVB(c) PVB(b)
PVB(b) PVB- (c) layer B Butyralization 68.5 68.5 68.5 68.5 68.5
65.5 65.5 68.5 degree (mol %) Acetylation 1 1 1 1 1 1 1 1 degree
(mol %) Content 100 100 100 100 100 100 100 100 (parts by weight)
Type of plasticizer DBA DBA DBA DBA DBA DBA DBA 3GO Content of
plasticizer 35 35 35 38 32 33 33 38.5 (parts by weight) Film
configuration B/A/B B/A/B B/A/B B/A/B B/A/B B/A/B B/A/B B/A/B Cloud
point measured using resin and 77 78 78 78 78 75 75 19 plasticizer
(.degree. C.) Peak temperature of tan .delta. at -3.1 -2.6 -2.9
-2.2 -2.8 -1.6 -3.1 -1.8 lower temperature side (.degree. C.)
Maximum value of peak of tan .delta. at 1.68 1.65 1.63 1.62 1.63
1.84 1.79 1.05 lower temperature side Maximum value of peak of tan
.delta. at 0.51 0.52 0.51 0.54 0.53 0.52 0.51 0.54 higher
temperature side Loss factor at 20.degree. C. near 3150 Hz 0.53
0.51 0.52 0.5 0.51 0.69 0.66 0.28 Loss factor at 30.degree. C. near
6300 Hz 0.17 0.16 0.17 0.16 0.16 0.24 0.22 0.09
EXPLANATION OF SYMBOLS
1. Interlayer film 1a. First surface 1b. Second surface 2. First
layer 2a. First surface 2b. Second surface 3. Second layer 3a.
Outer surface 4. Third layer 4a. Outer surface 11. Laminated glass
21. First component for laminated glass 22. Second component for
laminated glass
* * * * *